This question is too basic; it can be definitively and permanently answered by a single link to a standard internet reference source designed specifically to find that type of information.
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@FumbleFingers I don't know, I actually found it surprisingly hard to find a "legitimate" reference, as opposed to say UrbanDictionary, for this one.
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Evan HarperAug 28 '12 at 20:10

@cornbread ninja oh it's just people from a forum that I frequent.
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TheoAug 28 '12 at 21:28

@Evan Harper: On seconds thoughts, I think you've got a point! I just grabbed the UD link and a definition for the ostrich version in my first comment, but I see nothing making the fairly obvious connection between that and brown-nosing, kissing ass, and having your head up someone else's ass. Obvious or not, it doesn't seem to be explicitly set out anywhere else, so I shall vote to re-open.
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FumbleFingersAug 28 '12 at 23:49

This answer is insufficiently general. For instance, it would make sense to say, "He has his head so far up his ass that he didn't know his own sister had gotten married," although his sister's marriage is presumably not a problem.
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Evan HarperAug 28 '12 at 20:01